Liposomal Formulation Research Articles

A Comprehensive Review of Challenges in Oral Drug Delivery Systems and Recent Advancements in Innovative Design Strategies.

The oral route of drug administration is often preferred by patients and healthcare providers due to its convenience, ease of use, non-invasiveness, and patient acceptance. However, traditional oral dosage forms have several limitations, including low bioavailability, limited drug loading capacity, and stability and storage issues, particularly with solutions and suspensions. Over the years, researchers have dedicated considerable effort to developing novel oral drug delivery systems to overcome these limitations. This review discusses various challenges associated with oral drug delivery systems, including biological, pharmaceutical, and physicochemical barriers. It also explores common delivery approaches, such as gastroretentive drug delivery, small intestine drug delivery, and colon-targeting drug delivery systems. Additionally, numerous strategies aimed at improving oral drug delivery efficiency are reviewed, including solid dispersion, absorption enhancers, lipidbased formulations, nanoparticles, polymer-based nanocarriers, liposomal formulations, microencapsulation, and micellar formulations. Furthermore, innovative approaches like orally disintegrating tablets (ODT), orally disintegrating films (ODF), layered tablets, micro particulates, self-nano emulsifying formulations (SNEF), and controlled release dosage forms are explored for their potential in enhancing oral drug delivery efficiency and promoting patients' compliance. Overall, this review highlights significant progress in addressing challenges in the pharmaceutical industry and clinical settings, offering novel approaches for the development of effective oral drug delivery systems.

Drug-loaded liposomes for macrophage targeting in Mycobacterium tuberculosis: development, characterization and macrophage infection study.

This study investigates drug-loaded liposomes targeting macrophages as a promising strategy to enhance Tuberculosis (TB) treatment. The focus is on optimizing liposomal formulations for encapsulating OX-23, a previously identified anti-mycobacterial agent with a minimum inhibitory concentration (MIC) of 1.56µg/ml, and assessing their efficacy in macrophage infection models. Liposomal formulations were characterized for particle size, polydispersity index (PDI), and zeta potential using dynamic light scattering (DLS), with morphology analyzed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Macrophage infection assays, including those with the THP-1 macrophage cell line, were performed to evaluate the targeting efficiency and therapeutic potential of the formulations. Results showed that OX-23 could be successfully encapsulated in liposomes with various charges, achieving high encapsulation efficiency, optimal particle size, and acceptable PDI values. In-vitro studies with the THP-1 cell line demonstrated sustained release of the drug from the liposomes, with morphological analysis confirming that the liposomes were spherical and non-aggregated. The formulations exhibited significant penetration into infected macrophages and effectively inhibited the growth of intracellular Mycobacterium tuberculosis at the tested concentrations. These findings support the potential of liposomal OX-23 in targeting both extracellular and intracellular M. tuberculosis, offering a promising approach to TB treatment.

A step forwarded on the in vitro and in vivo validation of rifabutin-loaded liposomes for the management of highly virulent MRSA infections.

Staphylococcus aureus (S. aureus) infections, especially methicillin resistant (MRSA), constitute an alarming public health issue due to its association with high mortality, morbidity, and hospitalization costs. The increasing antibiotic resistance and biofilm-associated infections of MRSA prompted the discovery of novel and more effective therapeutic strategies. Our team has been working on alternative therapies against S. aureus infections. For this, we have been repurposing an existing antibacterial drug, rifabutin (RFB), through its association to a nanotechnological platform, liposomes, aiming to promote a preferential targeting to infected sites and maximizing its potential antibacterial effect. The therapeutic potential of RFB formulations against a MRSA commercial strain (MRSA ATCC®-33592), either in planktonic or biofilm forms, was assessed. RFB displayed higher antibacterial effects towards biofilm than vancomycin (VCM), the gold standard treatment against MRSA infections, with MBIC50 values of 103 and > 800 μg/ml, respectively. Moreover, the antimicrobial effect of RFB-loaded liposomes demonstrated to be lipid composition-dependent based on MIC50 and MBIC50 values, which was also confirmed by confocal laser scanning microscopy. These studies supported that for positively charged RFB liposomes an electrostatic interaction at biofilm surface occurs without internalization. On the other hand, for RFB-loaded liposomes with neutral surface charge a high internalization within the biofilm was observed. Moreover, this RFB liposomal formulation has also demonstrated to be stable in human plasma, as more than 83 % of RFB was still associated to liposomes 24 h after incubation at 37 °C. The proof of concept of RFB formulations was assessed in MRSA systemic murine models of infection. Therapeutic effect and survival rates were evaluated for animals induced and treated with RFB in free and liposomal forms and compared with negative and positive controls. For the lower infection murine model, 100 % survival was achieved for all groups under study. However, in a higher infection model only for the group of animals treated with RFB incorporated in liposomes a 100 % survival was attained. In terms of bacterial burden, RFB formulations exhibited lower levels when compared to VCM, even using a lower therapeutic dose: 20 vs 40 mg/kg of body weight, respectively. Overall, RFB constitutes an alternative and effective therapeutic strategy towards MRSA infections, being this effect potentiated through its association to a lipid nanoplatform.

P-2135. Assessing Diagnostic Capabilities and Treatment Accessibility for Invasive Fungal Infections in the Balkan Region

Abstract Background Ongoing progress in diagnosing and treating invasive fungal infections (IFI) faces challenges due to economic inequalities. Moreover, IFI prevalence and features vary between regions and countries. This study aims to assess the current diagnostic and treatment resources for IFIs in the Balkan region. Methods Data from Albania, Bosnia and Herzegovina, Bulgaria, Croatia, Greece, Kosovo, Moldova, Montenegro, North Macedonia, Serbia, Slovenia, and Romania were collected. The survey investigated participating institutions' traits, their views on IFIs, and the accessibility of diagnostic tools like microscopy, culture, serology, antigen detection, molecular testing, and therapeutic drug monitoring. Results Results from the survey revealed that among the 47 representatives from medical centres in the Balkans, 38% considered the incidence of IFIs to be low, while 34% perceived it as very low. Candida spp. was reported as the causative agent of IFIs in all surveyed centres (100%), followed by Aspergillus spp. (72%) and Cryptococcus spp. (43%). Diagnostic resources in the centres were as follows: 98% had access to culture and microscopy, and 93% had susceptibility testing technology. Antigen detection tests were used in 81% of the centres, while PCR tests were available in fewer centres: Aspergillus PCR (48%), Candida PCR (34%), Pneumocystis PCR (43%), and Mucorales PCR (19%). Among antifungal treatments, triazoles were the most prevalent, with 96% of centres offering them, followed by echinocandins (79%), mainly micafungin (77%), and amphotericin B (68%), primarily in its liposomal form (57%). Therapeutic drug monitoring was reported in 30% of surveyed centres, including voriconazole in all centres (100%), posaconazole in 71% of centres, itraconazole in 64% of centres, and flucytosine in 43% of centres. Conclusion In conclusion, mycology laboratories in Balkan centres are generally well-equipped, but molecular diagnostic tools are less accessible, present in fewer than half of the surveyed centres. Triazoles are the most accessible antifungal class, while other options like echinocandins, amphotericin B, flucytosine, and terbinafine are less widely available. The survey remains open to gather more insights from additional sites in the region. Disclosures Oliver A. Cornely, Prof. Dr., Abbott: Honoraria|Abbvie: Advisor/Consultant|Abbvie: Honoraria|AiCuris: Advisor/Consultant|Akademie fur Infektionmedizin: Honoraria|Al-Jazeera Pharmaceuticals/Hikma: Honoraria|amedes: Honoraria|AstraZeneca: Honoraria|Basilea: Advisor/Consultant|Biocon: Advisor/Consultant|BMBF: Grant/Research Support|Boston Strategic Partners: Advisor/Consultant|CIdara: Advisor/Consultant|CIdara: Expert Testimony|CIdara: Grant/Research Support|CIdara: Participation on a DRC or DSMB|CoRe Consulting: Stocks/Bonds (Private Company)|Deutscher Arzteverlag: Honoraria|DZIF: Grant/Research Support|EasyRadiology: Stocks/Bonds (Private Company)|EU-DG RTD: Grant/Research Support|F2G: Grant/Research Support|Gilead: Advisor/Consultant|Gilead: Grant/Research Support|Gilead: Honoraria|Grupo Biotoscana/United Medical/Knight: Honoraria|GSK: Advisor/Consultant|GSK: Honoraria|IQVIA: Advisor/Consultant|IQVIA: Participation on a DRC or DSMB|Janssen: Advisor/Consultant|Janssen: Participation on a DRC or DSMB|Matinas: Advisor/Consultant|MedPace: Advisor/Consultant|MedPace: Grant/Research Support|MedPace: Participation on a DRC or DSMB|Medscape/WebMD: Honoraria|MedUpdate: Honoraria|Menarini: Advisor/Consultant|Moderna: Honoraria|Molecular Partners: Advisor/Consultant|MSD: Grant/Research Support|MSD: Honoraria|MSG-ERC: Advisor/Consultant|Mundipharma: Advisor/Consultant|Mundipharma: Grant/Research Support|Mundipharma: Honoraria|Noscendo: Honoraria|Noxxon: Advisor/Consultant|Octapharma: Advisor/Consultant|Octapharma: Grant/Research Support|Pardes: Advisor/Consultant|Partner Therapeutics: Advisor/Consultant|Patent: US18/562644|Paul-Martini-Stiftung: Honoraria|Pfizer: Advisor/Consultant|Pfizer: Grant/Research Support|Pfizer: Honoraria|PSI: Advisor/Consultant|PSI: Participation on a DRC or DSMB|Pulmocide: Participation on a DRC or DSMB|Sandoz: Honoraria|Scynexis: Advisor/Consultant|Scynexis: Grant/Research Support|Seqirus: Advisor/Consultant|Seqirus: Honoraria|Seres: Advisor/Consultant|Shionogi: Advisor/Consultant|Shionogi: Honoraria|streamedup!: Honoraria|The Prime Meridian Group: Advisor/Consultant|Touch Independent: Honoraria|Vitis: Honoraria

P-43. A Single Composite Peptide Vaccine Comprising Conserved Influenza Epitopes Formulated with ALFQ Adjuvant Induced Broadly Reactive Antibodies to Human, Avian, and Swine Influenza Viruses

Abstract Background Reassortant influenza strains containing genes from human, avian, and/or swine origin, have led to major outbreaks, such as the 2009 swine flu pandemic. The ongoing global spread of highly pathogenic avian influenza (HPAI) A/H5N1 virus among poultry highlights the risk of zoonotic transmission leading to pandemics. A universal influenza vaccine that generates broadly neutralizing antibodies against influenza viruses is crucial for preventing future pandemics. Previous studies with our unconjugated composite peptide vaccine (two-peptide combination), which targets multiple highly conserved epitopes on influenza virus, generated broadly reactive antibodies to human and avian strains, including HPAI A/H5N1 viruses. A single peptide vaccine approach offers formulation and scale-up advantages. Here, we demonstrate that a novel, unconjugated, single composite peptide vaccine comprising highly conserved epitopes of hemagglutinin (HA), neuraminidase (NA), and matrix (M1/M2/M2e), and a universal T cell epitope, formulated with the highly potent adjuvant Army Liposomal Formulation with QS21 (ALFQ), induced broadly reactive antibodies to human, avian, and swine influenza strains. Methods ICR mice were immunized intramuscularly on days 0, 21, and 35 with 2μg of composite influenza peptide vaccine LHNVD-110, formulated with ALFQ adjuvant. Isotype-specific IgG titers to peptides and influenza A (H1N1pdm09, H3N2, HPAI H5N1) and B (Victoria, Yamagata) viruses were analyzed by ELISA. Neutralizing titers were determined using the microneutralization assay and inhibition of HA using the HAI assay. Results Robust serum IgG1 antibodies to human, avian, and swine influenza A and B viruses were induced. Post-immunization serum demonstrated neutralization and HA inhibition of Group 1 and 2 influenza viruses. Conclusion An unconjugated single composite peptide vaccine comprising highly conserved HA, NA, and matrix epitopes, formulated with ALFQ adjuvant, generated broadly reactive antibodies to human, avian, and swine influenza strains and neutralized seasonal and pandemic strains. This single composite peptide vaccine provides a cost-effective, and easily scalable strategy towards a universal influenza vaccine to combat future pandemics. Disclosures All Authors: No reported disclosures

P-1086. COT-832, a Novel Polyene Macrolide Antifungal (I): In Vitro Antifungal Activity against Candida, Aspergillus, and Mucor, etc., Hemolytic Activity, and Cytotoxicity

Abstract Background A novel polyene macrolide antifungal, COT-832 was created by SHIONOGI through structurally modifying Amphotericin B(AmB). Invasive fungal infections are commonly treated with antifungal drugs such as azoles, polyenes, and echinocandins; however, their efficacy is limited and mortality rates remain high. Therefore, the development of more effective and safer antifungal drugs is needed. AmB is available in formulations such as Fungizone (FGZ), which utilizes a deoxycholic acid formulation, and AmBisome (L-AMB), which employs a liposome formulation. While these polyene antifungals exhibit activity against a wide range of fungal species, their usage is often discontinued due to the nephrotoxicity associated with AmB itself. This study aimed to evaluate the antifungal activity, hemolytic activity, and cytotoxicity of COT-832 in vitro. Methods Antifungal activity was assessed using the CLSI method on clinical isolates from Japan (2012-2016). Hemolysis activity was measured after applying compounds to 4% sheep red blood cells for 24 hours. Cytotoxicity was evaluated by applying compounds to HepG2 cells for 2 hours and measuring lactate dehydrogenase (LDH) levels in the supernatant with Cytotox96 assay for calculating cell survival rate. Results Antifungal activity: COT-832 exhibited MIC90 of 0.5-2 µg/mL against Aspergillus and Candida, matching AmB's MIC. It also showed efficacy against azole-resistant A. fumigatus and echinocandin-resistant C. glabrata. COT-832's MIC90 for Cryptococcus was 0.5 µg/mL, surpassing AmB. Similar MICs were observed for rare molds. Hemolytic activity: AmB caused hemolysis from 0.625 µg/mL, reaching 80% at 2.5 µg/mL. COT-832 displayed an 8% hemolysis rate at 2.5 µg/mL. Cytotoxicity: AmB reduced cell count from 2 µg/mL, while no noticeable decrease occurred with COT-832 up to 72 µg/mL. Conclusion COT-832 exhibits comparable antifungal activity to AmB while demonstrating reduced toxicity against various cells, up to a tenfold decrease compared to AmB. These findings suggest that COT-832 has potential for development as a safer polyene macrolide antifungal drug, offering potent antifungal activity across a wide range of fungal species. Disclosures Hideki Maki, PhD, Shionogi & Co., Ltd.: employee|Shionogi & Co., Ltd.: employee Yuri Nishiyama, MS, Shionogi & Co., Ltd.: employee Takafumi Ohara, n/a, Shionogi & Co., Ltd.: employee Hideki Sugimoto, n/a, Shionogi & Co., Ltd.: employee

A Review on Salicylic Acid Ethosomal Gel

The ethosomes are vesicular carrier comprise of hydroalcoholic or hydro/alcoholic/glycolic phospholipid in which the concentration of alcohols or their combination is relatively high. To provide continuous drug infusion through an intact skin, several transdermal therapeutic systems have been developed for topical application onto the intact skin surface to control the delivery of drug and its subsequent permeation through the skin tissue. Transdermal route is promising alternative to drug delivery for systemic effect. An attempt was made to formulate the highly efficient ethosomal drug delivery system and enalapril meleate is used as model drug. The following conclusion are drown from the result and discussion described in the previous chapter. Liposomal formulation was also prepared by the thin film hydration method. The techniques used were simple and reproducible. The prepared ethosomes were spherical and discrete in shape. The size of vesicles were found to be in the range of 3.26-5.79 μm, 0.716-1.301 μm and 5.32 μm for unsonicated ethosomes, sonicated ethosomes and liposomes respectively. However ethosomes prepared by sonication method were more uniform and smaller in size, which is essential for skin permeation. While comparing the entrapment efficiency, ethosomes containing 30% w/w ethanol and prepared by sonication showed highest value with respect to all other formulation, so it is concluded ethosomes prepared by sonication and containing 30% w/w ethanol as the best formulation considering all other aspects. The highest value of transdermal flux for sonicated ethosomes containing 30% w/w ethanol is the indication of complete and rapid penetration through the skin may be because of tiny vesicular size.

Characterization of insulin and bile acid complexes in liposome by different mass spectrometry techniques.

Insulin bound with ligand molecules can improve its bioavailability in oral formulations. In this work, the interactions between insulin and bile acids of taurocholic acid (TCA) and glycocholic acid (GCA) are characterized using different mass spectrometry (MS) methods. Electrospray (ESI)-MS analysis revealed that GCA and TCA could interact with insulin individually or together through non-covalent bonds, and the products included mGCA-insulin, nTCA-insulin, and mGCA-nTCA-insulin complexes. Their binding stoichiometry, relative intensity ratio (IRa), and binding affinity were determined. ESI-MS/MS data and the calculated association constants both suggest that TCA has stronger affinity to insulin than GCA. The mixtures of various insulin, GCA, andTCA complexes with different charge states were separated, and distinct trend lines were observed using ion mobility mass spectrometry (IMMS). Moreover, liposomes containing insulin and GCA and/or TCA were prepared, and directly characterized using ESI-MS, and the interaction products of insulin with GCA and TCA were found in the liposome formulation. AutoDock was used to simulate molecular binding and select binding sites between insulin and GCA or TCA to explore the interaction mechanisms. The findings in this work could help understand the mechanism of actionof insulin protection with bile acids in the body.

A New Means to Generate Liposomes by Rehydrating Engineered Lipid Nanoconstructs

The concept and feasibility of producing liposomes by rehydrating engineered lipid nanoconstructs are demonstrated in this study. Nanoconstructs of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) were produced using a microfluidic delivery probe integrated with an atomic force microscope. The subsequent rehydration of these POPC constructs led to the formation of liposomes, most of which remained adhered to the surface. The size (e.g., diameter) of the liposomes could be tuned by varying the lateral dimension of the lipid constructs. Hierarchical liposomal structures, such as pentagons containing five liposomes at the corners, could also be designed and produced by depositing lipid constructs to designated locations on the surfaces, followed by rehydration. This new means allows for regulating liposomal sizes, distributions, and compositions. The outcomes benefit applications of liposomes as delivery vehicles, sensors, and building blocks in biomaterials design. The ability to produce hierarchical liposomal structures benefits numerous applications such as proto-cell development, multiplexed bio-composite materials, and the engineering of local bio-environments.

Disclosing long-term tolerance, efficacy and penetration properties of hyaluronic acid-coated latanoprost-loaded liposomes as chronic glaucoma therapy.

Frequent topical administration of hypotensive eye drops in glaucoma patients may lead to the development of dry eye disease (DED) symptoms, because of tear film destabilization and the adverse effects associated with antiglaucoma formulations. To address all this, in the current study preservative-free latanoprost-loaded (0.005% w/v) synthetic phosphatidylcholine (1,2-dioleoyl-sn-glycero-3-phosphocholine 0.75% w/v, 1,2-dimyristoyl-sn-glycero-3-phosphocholine 0.25% w/v) liposomes dispersed in the mucoadhesive polymer hyaluronic acid (0.2% w/v), containing the osmoprotective ingredients betaine (0.40% w/v) and leucine (0.90% w/v) (LAT-HA-LIP), have been prepared and further characterised. Permeation and retention evaluations on a validated ex vivo porcine eye model revealed that the active metabolite latanoprost acid was quantified only starting from LAT-HA-LIP once passing conjunctiva, sclera and choroid compared to the marketed latanoprost (0.005% w/v) benchmark (MF). The liposomal formulation outperformed MF when applied to the corneal tissue. Additionally, distribution and interactions within corneal and scleral tissues were investigated by means of two-photon microscopy with liposomal formulations containing coumarin-6. Furthermore, acute and chronic tolerance studies on rabbits revealed no signs of discomfort or ocular damage. Schirmer's test, tear osmolarity, tear breakup time (TBUT) and fluorescence staining evaluated through the Oxford grading scale, were assessed as DED diagnostic parameters over a 25-day monitoring period; LAT-HA-LIP consistently maintained levels comparable to physiological solution (0.9% w/v NaCl) used as control, with a slight increase of TBUT values from day 15 (6.00±0.63s for control, 7.00±0.78s for LAT-HA-LIP at day 15, p=0.0066). A daily topical application of LAT-HA-LIP for 15 consecutive days, effectively lowered IOP in a sustained way (2.51-3.88mmHg mean IOP reduction over the 5-15-day period). These results highlight the clinical relevance of the proposed technological platform, able to provide IOP reduction during the simulated long-term administration and simultaneous ocular surface protection with potential for the treatment of glaucoma.

Isolation, characterization and liposome-loaded encapsulation of a novel virulent Salmonella phage vB-SeS-01

IntroductionSalmonella is a common foodborne pathogenic bacterium, displaying facultative intracellular parasitic behavior, which can help the escape against antibiotics treatment. Bacteriophages have the potential to control both intracellular and facultative intracellular bacteria and can be developed as antibiotic alternatives.MethodsThis study isolated and characterized vB-SeS-01, a novel Guernseyvirinae phage preying on Salmonella enterica, whose genome is closely related to those of phages SHWT1 and vB-SenS-EnJE1. Furthermore, nine phage-carrying liposome formulations were developed by film hydration method and via liposome extruder.Results and DiscussionPhage vB-SeS-01 displays strong lysis ability against 9 out of 24 tested S. enterica strains (including the pathogenic “Sendai” and “Enteritidis” serovars), high replicability with a burst size of 111 ± 15 PFU/ cell and a titre up to 2.1 × 1011 PFU/mL, and broad pH (4.0 ~ 13.0) and temperature (4 ~ 80°C) stabilities. Among the nine vB-SeS-01 liposome-carrying formulations, the one encapsulated with PC:Chol:T80:SA = 9:1:2:0.5 without sonication displayed the optimal features. This formulation carried up to 1011 PFU/mL, with an encapsulation rate of 80%, an average size of 172.8 nm, and a polydispersity index (PDI) of 0.087. It remained stable at 4°C and 23°C for at least 21 days and at 37°C for 7 days. Both vB-SeS-01 and vB-SeS-01-loaded liposomes displayed intracellular antimicrobial effects and could reduce the transcription level of some tested intracellular inflammatory factors caused by the infected S. enterica sv. Sendai 16,226 and Enteritidis 50041CMCC.

Dual ligand functionalized pH-sensitive liposomes for metastatic breast cancer treatment: in vitro and in vivo assessment.

This research demonstrates the design and development of a novel dual-targeting, pH-sensitive liposomal (pSL) formulation of 5-Fluorouracil (5-FU), i.e., (5-FU-iRGD-FA-pSL) to manage breast cancer (BC). The motivation to explore this formulation is to overcome the challenges of systemic toxicity and non-specific targeting of 5-FU, a conventional chemotherapeutic agent. The proposed formulation also combines folic acid (FA) and iRGD peptides as targeting ligands to enhance tumor cell specificity and penetration, while the pH-sensitive liposomes ensure the controlled drug release in the acidic tumor microenvironment. The physicochemical characterization revealed that 5-FU-iRGD-FA-pSL possesses optimal size, low polydispersity index, and favorable zeta potential, enhancing its stability and targeting capabilities. In vitro studies demonstrated significantly enhanced cellular uptake, cytotoxicity, and inhibition of cell migration in MCF-7 BC cells compared to free 5-FU and non-targeted liposomal formulations. DAPI staining revealed significant apoptotic features, including chromatin condensation (CC) and nuclear fragmentation (NF), with 5-FU-iRGD-FA-pSL inducing more pronounced apoptosis compared to 5-FU-pSL. Furthermore, in vivo analysis in a BC rat model showed superior anti-tumor efficacy, reduced systemic toxicity, and improved safety profile of the 5-FU-iRGD-FA-pSL formulation. This dual-targeting pSL system presents a promising approach for enhancing the therapeutic index of 5-FU, offering a potential strategy for more effective BC treatment.

Double Peptide-Functionalized Carboxymethyl Chitosan-Coated Liposomes Loaded with Dexamethasone as a Potential Strategy for Active Targeting Drug Delivery

Liposomes are intensively used as nanocarriers for biology, biochemistry, medicine, and in the cosmetics industry and their non-toxic and biocompatible nature makes these vesicles attractive systems for biomedical applications. Moreover, the conjugation of specific ligands to liposomes increases their cellular uptake and therapeutic efficiency. Considering these aspects, the aim of the present study was to obtain new formulations of cationic liposomes coated with dual-peptide functionalized carboxymethyl chitosan (CMCS) for the treatment of inner ear diseases. In order to achieve efficient active targeting and ensuring a high efficacy of the treatment, CMCS was functionalized with Tet1 peptide, to target specific ear cells, and TAT peptide, to ensure cellular penetration. Furthermore, dexamethasone phosphate was loaded as a model drug for the treatment of ear inflammation. The infrared spectroscopy confirmed the functionalization of CMCS with the two specific peptides. The mean diameter of the uncovered liposomes varied between 167 and 198 nm whereas the CMCS-coated liposomes ranged from 179 to 202 nm. TEM analysis showed the spherical shape and unilamellar structure of liposomes. The release efficiency of dexamethasone phosphate after 24 h from the uncoated liposomes was between 37 and 40% and it appeared that the coated liposomes modulated this release. The obtained results demonstrated that the liposomes are hemocompatible since, for a tested concentration of 100 µg/mL, the liposome suspension had a lysis of erythrocytes lower than 2.5% after 180 min of incubation. In addition, the peptide-functionalized CMCS-coated liposomes induced a non-significant effect on the viability of normal V79-4 cells after 48 h, at the highest doses. Values of 71.31% were recorded (CLCP-1), 77.28% (CLCP-2) and 74.36% (CLCP-3), correlated with cytotoxic effects of 28.69%, 22.72%, and 25.64%.

Intranasal liposomal remdesivir induces SARS-CoV-2 clearance in K18-hACE2 mice and ensures survival.

A huge challenge after the emergence of COVID-19 has been the discovery of effective antiviral drugs. Although remdesivir (RDV) emerged as one of the most promising drugs, its pharmaceutical formulation Veklury® is limited by moderate efficacy, high toxicity and need for parenteral administration. The aim of the present work was to develop a liposomal formulation of RDV for pulmonary administration and evaluate its efficacy in models of COVID-19. Liposomal RDV nanoformulation (LRDV) was selected based on high drug encapsulation efficiency, sustained drug release property and high in vitro selectivity index. A pharmacokinetic study of intranasal LRDV in mice demonstrated effective delivery of the drug to the lungs. LRDV was then evaluated for its efficacy in SARS-CoV-2-infected K18-hACE2 mice after repeated intranasal administration at 10mg/kg/bid for 5days. Veklury® given intraperitoneally at 20mg/kg/bid was used for comparison. Mice receiving LRDV remained alive up to 15days post-infection (dpi). On the other hand, the control groups receiving PBS and empty liposomes showed 100% death at 6 dpi and the Veklury® group had 62.5% death at 8 dpi. Intranasal LRDV also promoted a strong reduction in viral loads in the brain and lungs of mice and prevented the inflammatory response induced by SARS-CoV-2 in the lungs. This is in contrast with Veklury®, which did not significantly reduce the viral titer in the brain and was poorly effective in preventing the inflammatory response in the lungs. Intranasal LRDV emerges as a promising therapeutic strategy for COVID-19, including "Long COVID".

Optimized Rutin-incorporating PEGylated Nanoliposomes as a Model with Remarkable Selectivity Against PANC1 and MCF7 Cell Lines

This study aims to enhance the delivery of polyphenols using nanotechnology. To develop and evaluate liposomal formulations for improved delivery and stability of polyphenols, specifically focusing on Rutin. Liposomal formulations were meticulously prepared via the Thin-Film Hydration method. Comprehensive physical characterization was conducted, including stability assessments using Dynamic Light Scattering (DLS) and Thermogravimetric Analysis (TGA). The free radical scavenging activity was measured using the DPPH• assay, and MTT cell viability assays were performed to assess cytotoxicity. The results demonstrated a significant reduction in nanoparticle size from 123 nm to 116 nm and an increase in charge from -14 to -22 with rising Rutin concentrations. The formulation achieved enhanced homogeneity at a Rutin concentration of 2.0 mg/mL and showed higher stability. Incorporating Rutin improved the formulation's stability over 30 days, as evidenced by a decrease in the Differential Scanning Calorimetry peak temperature from 58.65 °C to 54.42 °C. Rutin-loaded and co-loaded nanoliposomes exhibited remarkable selectivity against PANK1 and MCF7 cell lines, with IC50 values of 2.13±0.35 μg/mL and 4.75±0.19 μg/mL, respectively. PEGylated Rutin-loaded nanoliposomes offer a promising platform for biodegradable and biocompatible drug delivery systems, enhancing the bioavailability, solubility, and stability of the polyphenols.

Effects of Lipid Headgroups on the Mechanical Properties and In Vitro Cellular Internalization of Liposomes.

We performed all-atom and coarse-grained simulations of lipid bilayer mixtures of the unsaturated lipid DOPC, with saturated lipids having the same 18-carbon acyl tails and different headgroups, to understand their mechanical properties. The secondary lipids were DSPG, DSPA, DSPS, DSPC, and DSPE. The DOPC:DSPG system with 65:35 molar ratio was the softest, with area compressibility modulus KA ∼ 22% smaller than the pure DOPC value. Raising the mole % of DOPC leads to increases in KA, yet at any given composition the KA trend is DSPG < DSPA < DSPS < DSPC < DSPE. Lipid-lipid interactions are weaker in DOPC:DSPG mixtures and stronger in DSPE systems. The head and phosphate groups of the secondary lipids DSPG, DSPA, and DSPS interact strongly with salt ions. Adding secondary lipids leads to DOPC having more ordered acyl tails relative to pure DOPC systems. No evidence of phase separation or inhomogeneities was observed in our simulations. We synthesized three liposomal formulations, L-DOPC (pure DOPC) and L-DOPC/DSPG and L-DOPC/DSPA, both with 15 mol % of secondary lipid. L-DOPC/DSPA had approximately 3- and 2-times higher in vitro internalization by normal epithelial (EpH4-Ev) and metastatic breast cancer (4T1) cells, compared with L-DOPC. The uptake of L-DOPC/DSPG by EpH4-Ev cells was almost 2-fold compared to L-DOPC, but both liposomes had similar uptakes by cancer cells. As L-DOPC/DSPG and L-DOPC/DSPA have similar KA values, we presumed that the mechanical properties, possibly in combination with the higher negative surface charges in L-DOPC/DSPA and differences in effective liposome diameters and diffusivities, contributed to these observations.

Investigation into Alzheimer's-related amyloid-β conformational transformations and stability influenced by green iron oxide nanoparticles (GIONP).

Alzheimer's disease (AD) is popularly believed to be triggered by the aggregation of amyloid beta 1-42 (Aβ-42) peptides, eventually leading to neurodegeneration. Our study delves into the influential role played by Green Iron Oxide Nanoparticles (GIONP). GIONP are typically synthesized using a green chemistry approach, imposing curcumin as a biocompatible reducing and capping agent, leveraging its inherent antioxidant, anti-inflammatory, and neuroprotective attributes. Herein, our research particularly aims to decipher whether GIONP modulates the secondary structure of Aβ1-42 peptides with a close consideration to the surrounding physiological factors, as well as the membrane bilayer probable conformation changes. Raman spectroscopy was employed to investigate the interaction between GIONP and Aβ1-42 aggregates, demonstrating significant alterations in secondary structure dynamics of Aβ1-42 polypeptide. Fourier-transform infrared (FTIR) spectroscopy shed light on the chemical interactions between GIONP and curcumin, a capping agent. X-ray diffraction (XRD) analysis was performed to determine the crystalline structure and phase purity of the synthesized GIONP, providing insights into their stability and structural integrity. GIONP particle size distribution investigations and membrane architectures surrounding GIONP were carried out for their impact on membrane integrity and stability. The morphology of GIONP, membrane mimetic liposomal structures formation, and integrity were studied using transmission electron microscopy (TEM), accompanied with energy-dispersive X-ray spectroscopy (EDS), which displayed the elements distribution within each of the structures. The study uncovered that GIONP stabilizes the secondary structure of Aβ1-42, potentially offering modulation to the aggregation process. Furthermore, GIONP proved to have no negative impact on membrane integrity, implying that they could be safely employed as a therapeutic option for the modulation of peptide aggregation's pathological pathway of Alzheimer's disease. This study may contribute to broadening our understanding of nanoparticle-mediated therapies in modulating neurodegenerative disorders, highlighting their dual involvement in amyloid aggregation regulation and membrane structure maintenance.

SiRNA Knocking Down in HepG2 Cells Identifies PFKFB4 and HNF4α as Key Genes Important for Cancer Cell Survival.

Liposomes are versatile delivery systems for encapsulating small interfering RNAs (siRNAs) because they enhance cellular uptake and gene silencing. This study compares the new liposome formula to commercial lipofectamine in delivering siRNAs targeting hepatic carcinoma genes, focusing on HNF4-α and PFKFB4. Flow cytometry and confocal microscopy revealed efficient internalization of PE-Rhod- B labeled lipoplexes in HepG2 cells, while cytotoxicity assays demonstrated significant reductions in cell viability, particularly with siHNF4-α and siPFKFB4. The newly formulated liposomes showed superior efficacy, achieving nearly 93% cytotoxicity at 100 nM, compared to just 50% with lipofectamine at the same concentration. Furthermore, real-time PCR confirmed that the liposome-encapsulated siHNF4-α reduced HNF4-α mRNA expression by tenfold at 100 nM, compared to a twofold reduction with lipofectamine at 200 nM. Similarly, siPFKFB4 delivered via liposomes showed a dose-dependent 35-fold reduction in PFKFB4 mRNA expression at 100 nM, outperforming the maximum reduction achieved by lipofectamine. The IC50 values for all siRNA treatment groups were significantly lower when using the liposome formula, reflecting improved delivery efficiency. These results demonstrate the potential of liposome formulations for therapeutic siRNA delivery. The encapsulation enhances cellular uptake and gene silencing efficiency, making the liposome formula a promising candidate for targeted gene therapy in hepatic carcinoma. Further research should explore it's in vivo biodistribution and potential combination therapies.

Formulation and Evaluation of Liposomal Cream Containing Tolnaftate

The current study’s objective was to formulate and evaluate a liposomal cream containing tolnaftate in order to improve the drug’s bioavailability. Tolnaftate is a drug having low permeability which results in decreased drug absorption and so is the bioavailability. To overcome these problems tolnaftate is incorporated in liposomes. Liposome vesicular drug delivery system was preferred due to its greater solubility, permeability and bioavailability. It carries a substantial amount of drug which increased the drug’s penetration. The liposomes were prepared using a variety of phospholipids, specifically soy lecithin and egg phosphatidylcholine in varying ratios. Liposomes were prepared by ethanol injection method and evaluated for morphology, percentage practical yield, percentage entrapment efficiency, drug content and in-vitro drug release study. The formulation with the best result according to the evaluation parameters was F2 with greater percentage drug entrapment, drug content and in-vitro drug release was considered to be optimized formulation and this F2 formulation was further evaluated by SEM, DSC and XRD. Liposomal cream was formulated using the optimized formulation. Spreadability, Viscocity, pH measurement and in-vitro drug release were evaluated for liposomal cream. Formulation F2 and optimized liposomal cream formulation showed in-vitro drug release of 92.44% and 77.48% respectively at the end of 8th hour. Keywords: Tolnaftate, liposomes, SEM, DSC, XRD

Liposomal Drug Delivery: Comparative Kinetics, Efficacy, and Applications in Targeted Therapeutics

During the Second World War, in order to reduce infections in soldiers wounds, nurses had to inject the injured with multiple shots of penicillin per day because one single shot of penicillin only lasts a short period of time, but the lack of human resources prevented some of the wounded soldiers from receiving the dose of penicillin that they needed[1]. To reduce the need for human labor in penicillin intake, Romansky discovered that mixing penicillin with lipids would prolong the time in which penicillin has effect. This innovation saved a lot of people from infection at the time. Lipid-based drug carriers have been developed and innovated even more throughout the years.A few years ago, the COVID-19 pandemic has facilitated advancements in vaccination technologies, including the use authorization of mRNA vaccines encapsulated in lipid nanoparticles. Traditional drug delivery methods, such as oral intake, injection, and transdermal applications, usually face challenges like low accuracy, toxicity, and variable effectiveness. However, liposomes, discovered in the 1960s, emerged as a drug carrier that, due to their specific structure, allowed for prolonged and site-specific drug release. Liposomes can encapsulate drugs of different molecular qualities, allowing lipid-based drug carriers to have excellent performance in carrying both hydrophobic and hydrophilic drugs. This paper examines the composition of liposomes, the different factors of the lipid bilayers, and the release kinetics in drug delivery. Using a hybrid modeling approach of first-order kinetics and the Higuchi model, the study simulates drug release profiles. The liposomal formulation of drugs demonstrates the potential of lipid-based delivery systems in enhancing the efficacy while minimizing side effects of treatments.